Polishing machine

ABSTRACT

A polishing machine includes a housing, a motor, a main shaft rotatable about a first axis, a first execution assembly for connecting to a first accessory, wherein the first execution assembly includes a first rotation member and a first output, the first rotation member is configured for connecting to the main shaft and is movable about the first axis under driving of the main shaft in response to connecting to the main shaft, the first output member includes a first driving portion for connecting to the first accessory and is rotatable relative to the first rotation member about a second axis, and a limiting member movable between a first position at which the first rotation member is prevented from moving relative to the main shaft and a second position at which the first rotation member is allowed to move relative to the main shaft.

RELATED APPLICATION INFORMATION

This application claims the benefit under 35 U.S.C. § 119(a) of Chinese Patent Application No. CN 201910516067.3, filed on Jun. 14, 2019, and Chinese Patent Application No. CN 201910664593.4, filed on Jul. 23, 2019, each of which is incorporated by reference in its entirety herein.

TECHNICAL FIELD

The present disclosure relates to an electric tool, and more particularly to a polishing machine.

BACKGROUND

Before polishing workpieces such as automobiles and parts, users usually need to sand the scratches and rough parts on the workpieces. Therefore, users may need multiple tools to realize the work on the workpieces at the same time, which not only increases the cost, but also lower the work efficiency.

SUMMARY

In one aspect of the disclosure, a polishing machine includes a housing, a motor, a first execution assembly, a second execution assembly, a limiting member and an operation member. The housing includes a handle portion for a user gripping. The motor is disposed in the housing. The main shaft is rotatable relative to the housing about a first axis. The first execution assembly is configured for connecting to a first accessory, where, the first execution assembly includes a first rotation member and a first output member, the first rotation member is configured for connecting to the main shaft and is rotatable about the first axis under driving of the main shaft in response to connecting to the main shaft; the first output includes a first driving portion for connecting to the first accessory so as to drive the first accessory to rotate about a second axis; the second axis coincides with the first axis. The second execution assembly is configured for connecting to a second accessory, where, the second execution assembly includes a second rotation member and a second output member, the second rotation member is configured for connecting to the main shaft and is rotatable about the first axis under driving of the main shaft in response to connecting to the main shaft; the second output member includes a second driving portion for connecting to the second accessory to drive the second accessory, the second output member is rotatable relative to the second rotation member about a third axis; the third axis is parallel to the first axis, and a distance between the third axis and the first axis is greater than or equal to 1 mm and less than or equal to 12 mm. The limiting member is movable between a first position and a second position, where, the limiting member is configured to, in condition that the limiting member is at the first position, prevent the first rotation member or the second rotation member from moving relative to the main shaft; and the limiting member is further configured to, in condition that the limiting member is at the second position, allow the first rotation member or the second rotation member to move relative to the main shaft. And the operation member configured to, in condition that the operation member is operated, allow the limiting operation to disengage from the first position.

In another aspect of the disclosure, a polishing machine includes a housing, a motor, a first execution assembly, a second execution assembly, a limiting member and an operation member. The housing includes a handle portion for a user gripping. The motor is disposed in the housing. The main shaft is rotatable relative to the housing about a first axis. The first execution assembly is configured for connecting to a first accessory, where, the first execution assembly includes a first rotation member and a first output member, the first rotation member is configured for connecting to the main shaft and is rotatable about the first axis under driving of the main shaft in response to connecting to the main shaft; the first output includes a first driving portion for connecting to the first accessory to drive the first accessory, the first output member is rotatable relative to the first rotation member about a second axis, the second axis is parallel to the first axis, and a distance between the second axis and the first axis is greater than or equal to 1 mm and less than or equal to 3 mm. The second execution assembly is configured for connecting to a second accessory, where, the second execution assembly includes a second rotation member and a second output member, the second rotation member is configured for connecting to the main shaft and is rotatable about the first axis under driving of the main shaft in response to connecting to the main shaft; the second output member includes a second driving portion for connecting to the second accessory to drive the second accessory, the second output member is rotatable relative to the second rotation member about a third axis; the third axis is parallel to the first axis, and a distance between the third axis and the first axis is greater than or equal to 1 mm and less than or equal to 12 mm. The limiting member is movable between a first position and a second position, where, the limiting member is configured to, in condition that the limiting member is at the first position, prevent the first rotation member or the second rotation member from moving relative to the main shaft; and the limiting member is further configured to, in condition that the limiting member is at the second position, allow the first rotation member or the second rotation member to move relative to the main shaft. And the operation member configured to, in condition that the operation member is operated, allow the limiting operation to disengage from the first position.

In another aspect of the disclosure, a polishing machine includes a housing, a motor, a first execution assembly, a limiting member and an operation member. The housing includes a handle portion for a user gripping. The motor is disposed in the housing. The main shaft is rotatable relative to the housing about a first axis. The first execution assembly is configured for connecting to a first accessory, where, the first execution assembly includes a first rotation member and a first output member, the first rotation member is configured for connecting to the main shaft and is rotatable about the first axis under driving of the main shaft in response to connecting to the main shaft; the first output includes a first driving portion for connecting to the first accessory to drive the first accessory, the first output member is rotatable relative to the first d rotation member about a second axis; the second axis is parallel to the first axis, and a distance between the second axis and the first axis is greater than or equal to 1 mm and less than or equal to 12 mm. The limiting member is movable between a first position and a second position, where, the limiting member is configured to, in condition that the limiting member is at the first position, prevent the first rotation member from moving relative to the main shaft; and the limiting member is further configured to, in condition that the limiting member is at the second position, allow the first rotation member to move relative to the main shaft. And the operation member is configured to, in condition that the operation member is operated, allow the limiting operation to disengage from the first position.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a plan view illustrating a polishing machine according to an example;

FIG. 2 is a top view illustrating a main engine in FIG. 1;

FIG. 3 is a sectional view illustrating the main engine, a first execution assembly, a second execution assembly, and a third execution assembly in FIG. 1;

FIG. 4 is an enlarged view illustrating partial structure in FIG. 3, where a limiting member is in a first position;

FIG. 5 is a sectional view illustrating a main shaft, a driving member and the limiting member in FIG. 4 when the main shaft is installed with a first execution assembly;

FIG. 6 is an enlarged view illustrating some structures in FIG. 3, where the limiting member is in a second position;

FIG. 7 is a sectional view illustrating the main shaft, the driving member and the limiting member in FIG. 6 when the main shaft is installed with the first execution assembly;

FIG. 8 is a plan view illustrating the first execution assembly in FIG. 1;

FIG. 9 is a plan view illustrating the driving member in FIG. 3;

FIG. 10 is a plan view illustrating the main engine in FIG. 1 without a housing;

FIG. 11 is a perspective view illustrating the structure shown in FIG. 10;

FIG. 12 is an exploded view illustrating a motor and an air guiding cover in FIG. 11;

FIG. 13 is a perspective view illustrating the main engine in FIG. 1; and

FIG. 14 is an enlarged view illustrating partial region in FIG. 13.

DETAILED DESCRIPTION

As shown in FIG. 1 to FIG. 3, a polishing machine includes a main engine 10 a and a first execution assembly 50. The main engine 10 a includes a housing 11, a motor 12 and a main shaft 13. The first execution assembly 50 is configured for connecting to a first accessory 50 a, so that the main engine 10 a outputs the power to the first execution assembly 50, and the first execution assembly 50 drives the first accessory 50 a to move so as to realize a first function such as sanding, polishing and waxing. The housing 11 includes a handle portion 111 for a user gripping.

The motor 12 is disposed in the housing 11. The main shaft 13 is rotatable about a first axis 101 relative to the housing 11, and the main shaft 13 outputs the power when the main shaft 13 is rotating. The main engine 10 a may be detachably connected to the first execution assembly 50, thereby facilitating the user to replace different execution assembly according to the needs. The polishing machine 100 further includes a second execution assembly 60 for connecting to a second accessory 60 a. When the first execution assembly 50 is disassembled, the user may connect the second execution assembly 60 to the main engine 10 a, so that the main engine 10 a outputs the power to the second execution assembly 60, and the second execution assembly 60 drives the second accessory 60 a to move to realize the second function different from the first function. It can be understood that, the first function may be one or more of the following: sanding, polishing and waxing, and the second function may also be one or more of the following: sanding, polishing and waxing. Both the first function and the second function may be sanding, polishing or waxing. In one example, both the first function and the second function are sanding; the difference is that, the first function may realize sanding with a first precision, and the second function may realize sanding with a second precision.

The polishing machine 100 further includes a third execution assembly 70 for connecting to a third accessory 70 a. When the first execution assembly 50 or the second execution assembly 60 is disassembled, the user may connect the third execution assembly 70 to the main engine 10 a, so that the main engine 10 a outputs the power to the third execution assembly 70, and the third execution assembly 70 drives the third accessory 70 a to move to realize a third function.

When the user needs to perform three processes, namely sanding, polishing and waxing, on the automobiles and the workpieces, the user only needs one polishing machine 100 installed with different execution assemblies to complete the three processes, which facilities the user's operation, saves the cost and improves the work efficiency.

In the present example, the main engine 10 a further includes an installation assembly 20 for detachably installing the above-mentioned first execution assembly 50, the second execution assembly 60 or the third execution assembly 70 to the main shaft 13. As shown in FIG. 3 and FIG. 4, the installation assembly 20 includes a limiting member 21 and an operation member 22. The limiting member 21 is configured for locking or releasing the first execution assembly 50, the second execution assembly 60 or the third execution assembly 70. The operation member 22 is configured for the user to operate so that the limiting member 21 releases the first execution assembly 50, the second execution assembly 60 and the third execution assembly 70.

The first execution assembly 50 includes a first rotation member 51 and a first output member 52. The first rotation member 51 is configured for connecting to the main shaft 13. The first rotation member 51 may be driven by the main shaft 13 to rotate about the first axis 101 when the first rotation member 51 is connected to the main shaft 13, and the first rotation member 51 is a rotation shaft. The first output member 52 includes a first driving portion 521 for connecting to the first accessory 50 a, and the first driving portion 521 may drive the first accessory 50 a to rotate about a second axis 102, where the second axis 102 coincides with the first axis 102. The first driving portion 521 is a hole or a post centered on the second axis 102. In the present example, the first rotation member 51 and the first output member 52 are integrally formed. In this way, when the first rotation member 51 is driven by the main shaft 13 to rotate about the first axis 101, the first output member 52 drives the first accessory 50 a to rotate about the first axis 101. The first accessory 50 a is centered on the first axis 101, and the first execution assembly 50 drives the first accessory 50 a to rotate without eccentricity.

The second execution assembly 60 includes a second rotation member 61 and a second output member 62. The second rotation member 61 is configured for connecting to the main shaft 13. The second rotation member 61 may be driven by the main shaft 13 to rotate about the first axis 101 when the second rotation member 61 is connected to the main shaft 13, and the second rotation member 61 is a rotation shaft. The second output member 62 includes a second driving portion 621 for connecting to the second accessory 60 a, and the second driving portion 621 may drive the second accessory 60 a to rotate. The second output member 62 is rotatably connected to the second rotation member 61, and the second output member 62 is rotatable about a third axis 103 relative to the second rotation member 61. A distance L1 between the third axis 103 and the first axis 101 is greater than or equal to 1 mm, and less than or equal to 12 mm. The second driving portion 621 is a hole or a post centered on the third axis 103. In the present example, since the second output member 62 is connected to the second rotation member 61, the second output member 62 simultaneously drives the second accessory 60 a to revolve around the first axis 101 when the second rotation member 61 is rotated about the first axis 101. When the polishing machine 100 is turned on to perform the work on the workpiece, the second output member 62 drives the second accessory 60 a to revolve around the first axis 101 under the driving of the second rotation member 61; at the same time, since the second accessory 60 a is in contact with the workpiece, the workpiece generates a friction force on the second accessory 60 a, and the friction force drives a whole formed by the second accessory 60 a and the second output member 62 to rotate about the third axis 103 relative to the second rotation member 61. That is to say, when the main engine 10 a is installed with the second execution assembly, the second accessory 60 a rotates about the third axis 103 while revolving around the first axis 101. In the present example, the second rotation member 61 is further connected with a second counterweight 63, so as to improve the balance of the polishing machine 100 when the second execution assembly 60 is installed.

The third execution assembly 70 includes a third rotation member 71 and a third output member 72 which are configured for connecting to the main shaft 13. The third rotation member 71 is configured for connecting to the main shaft 13. The third rotation member 71 may be driven by the main shaft 13 to rotate about the first axis 101 when the third rotation member 71 is connected to the main shaft 13, and the third rotation member 71 is a rotation shaft. The third output member 72 includes a third driving portion 721 for connecting to the third accessory 70 a, and the third driving portion 721 may drive the third accessory 70 a to rotate. The third output member 72 is rotatably connected to the third rotation member 71, and the third output member 72 is rotatable about a fourth axis 104 relative to the third rotation member 71. A distance L2 between the fourth axis 104 and the first axis 101 is greater than or equal to 1 mm, and less than or equal to 3 mm. The third portion 721 is a hole or a post centered on the fourth axis 104. In the present example, since the third output member 72 is connected to the third rotation member 71, the third output member 72 simultaneously drives the third accessory 70 a to revolve around the first axis 101 when the third rotation member 71 is rotated about the first axis 101. When the polishing machine 100 is turned on to perform the work on the workpiece, the third output member 72 drives the third accessory 70 a to revolve around the first axis 101 under the driving of the third rotation member 71; at the same time, since the third accessory 70 a is in contact with the workpiece, the workpiece generates a friction force on the third accessory 70 a, and the friction force drives a whole formed by the third accessory 70 a and the third output member 72 to rotate about the fourth axis 104 relative to the third rotation member 71. That is to say, when the main engine 10 a is installed with the third execution assembly, the third accessory 70 a rotates about the fourth axis 104 while revolving around the first axis 101. In the present example, the third rotation member 71 is further connected with a third counterweight 73, so as to improve the balance of the polishing machine 100 when the third execution assembly 70 is installed.

As shown in FIG. 3 to FIG. 7, the limiting member 21 is movable between a first position in which the first rotation member 51 is prevented from moving relative to the main shaft 13 and a second position in which the first rotation member 51 is allowed to move relative to the main shaft 13. The operation member 22 is operatable by the user. When the operation member 22 is operated by the user to slide upward along the first axis 101 relative to the housing 11, the operation member 22 may drive the limiting member 21 to disengage from the first position, so that the first rotation member 51 may be disassembled from the main shaft 13 by the user. Similarly, when the main engine 10 a is installed with the second execution assembly 60, the second rotation member 61 is prevented from moving relative to the main shaft 13 when the limiting member 21 is located in the first position, and the second rotation member 61 is allowed to move relative to the main shaft 13 when the limiting member 21 is located in the second position. When the main engine 10 a is installed with the third execution assembly 70, the third rotation member 71 is prevented from moving relative to the main shaft 13 when the limiting member 21 is located in the first position, and the third rotation member 71 is allowed to move relative to the main shaft 13 when the limiting member 21 is located in the second position. In the present example, the first rotation member 51, the second rotation member 61 and the third rotation member 71 each may be formed as a cooperating structure with substantially the same structure, and the cooperating structure is cooperated with the limiting member 21.

As shown in FIG. 8, taking the first execution assembly 50 as an example, the cooperating structure formed on the first rotation member 51 is a first groove 511. The limiting member 21 is a sphere, part of which can be inserted into the first groove 511. The main shaft 13 is formed with a driving hole 131 centered on the first axis 101. The driving hole 131 is configured for the first rotation member 51 inserting into, and a hole wall of the driving hole 131 is formed with an accommodating hole 132 for accommodating the sphere. The accommodating hole 132 penetrates through the driving hole 131 along a first straight line 105, where the first straight line 105 is perpendicular to the first axis 101. The first straight line 105 may be a radial direction of the first axis 101. The sphere may move to the first position and the second position in the accommodating hole 132 along the first straight line 105. As shown in FIG. 4, FIG. 5 and FIG. 8, when the limiting member 21 is located in the first position, part of the limiting hole 21 extends into the driving hole 131 and is inserted into the first groove 511, so that the limiting member 21 limits the first rotation member 51 to slide along the first axis 101, thereby preventing the first rotation member 51 from disengaging from the main shaft 13 along the first axis 101. As shown in FIG. 6 to FIG. 8, when the limiting member 21 is located in the second position, the limiting member 21 is located outside the driving hole 131, and disengaged from the first groove 51, so that the limiting member 21 no longer limits the first rotation member 51 to slide along the first axis 101, thereby allowing the first rotation member 51 to disengage from the main shaft 13 along the first axis 101. Similarly, when the limiting member 21 is located in the first position, the limiting member 21 is inserted into the first groove 51, and further limits the first rotation member 51 to rotate relative to the main shaft 13, so that the main shaft 13 may output the power to the first rotation member 51 through the limiting member 21 so as to drive the first rotation member 51 to rotate about the first axis 101.

The polishing machine 100 further includes a transmission assembly 14 and an inner housing 15. The transmission assembly 14 is configured to transmit the power between the motor 12 and the main shaft 13. The inner housing 15 is disposed in the housing 11, and configured for accommodating the transmission assembly 14.

The housing 11 includes a head housing 112 located at a front end of the handle portion 111 and a coupling portion 113 located at a rear end of the handle portion 113. The head housing 112 is configured for accommodating the main shaft 13. The coupling portion 113 is configured for installing a battery pack 16. The battery pack 16 is connected to the housing 11 to supply power to the motor 12. The motor 12 is disposed in the handle portion 111. The motor 12 includes a motor shaft 121 rotatable about a rotation axis 106, the motor shaft 121 is connected to the transmission assembly 14, and the transmission assembly 14 is connected to the main shaft 13, so that the transmission assembly 14 may transmit the power outputted by the motor shaft 121 to the main shaft 13. The rotation axis 106 is perpendicular to the first axis 101. Part of the inner housing 15 is disposed in the head housing 112, and the inner housing 15 accommodates the transmission assembly 15 and further accommodates part of main shaft 13. One part of the main shaft 13 is disposed in the inner housing 15, and other part of the main shaft 13 extends out of the inner housing 15. The limiting member 21 is located in the housing 11, and also located outside the inner housing 15. The operation member 22 is located outside the housing 11. One part of the operation member 22 extends into the housing 11, and does not extend into the inner housing 15, so that both the operation member 22 and the limiting member 21 are located outside the inner housing 15, so that the inner housing 15 can effectively seal the transmission assembly 14 located in the inner housing 15 from dust and water.

The installation assembly 20 further includes a first biasing element 23, a driving member 24 and a second biasing element 25. The first biasing element 23 biases the operation member 22 to generate a biasing force for driving the operation member 22 to reset. The first biasing element 23 is a first spring, part of which is sleeved outside the head housing 112, and the first spring is located between the head housing 112 and the operation member 22. One end of the first spring biases the head housing 112, another end of the first spring biases the operation member 22. The operation member 22 surrounds the first axis 101 and is a sleeve, and the operation member 22 is sleeved outside the head housing 112, so that the operation member 22 may slide along the first axis 101 relative to the head housing 112. A guiding member 114 is fixed at a lower end of the head 112. The guiding member 114 is made of metal, and the guiding member 114 guides the operation member 22 to slide along the first axis 101, so that the operation member 22 slides more smoothly. The head housing 112 is made of plastic, and the guiding member 114 is a metal member, thereby avoiding a situation that the operation member 22 slides non-smoothly and the head housing 112 is deformed or damaged caused by directly guiding the operation member 22 by the head housing 112. Both the operation member 22 and the guiding member 114 surround the first axis 101, the guiding member 114 protrudes downward out of the head housing 112. One part of the first spring is sleeved onto the head housing 112, and the other part of the first spring is sleeved outside the guiding member 114. Similarly, one part of the operation member 22 is sleeved onto the head housing 112, and the other part of the operation member 22 is sleeved outside the guiding member 114. The operation member 22 further protrudes downward out of the guiding member 114, so that both the guiding member 114 and the operation member 22 may play a role of protecting the user. The limiting member 21 is disposed outside the inner housing 15, and the guiding member 114 is fixedly connected to the head housing 112. The guiding member 114 further includes a covering portion 114 a, and the covering portion 114 a covers part of an opening 112 a of the head housing 112 open downward, so that the guiding member 114 may effectively protect the limiting member 21 which is located outside the inner housing 15 and inside the housing 11.

The driving member 24 is configured for contacting with the limiting member 21 to drive the limiting member 21 to move to the first position, and the second biasing element 25 generates a biasing force for driving the limiting member 21 to move toward the first position. As shown in FIG. 7 and FIG. 9, in one example, the driving member 24 is a sleeve sleeved onto the main shaft 13, and a driving surface 241 is formed on the driving member 24. The second biasing element 25 is a second spring sleeved onto the main shaft 13, and the second spring biases the sleeve to drive the sleeve to move toward a position in where the driving surface 241 is in contact with the limiting member 21.

The operation member 22 is further formed with a contact portion 221 which is in contact with the sleeve, and the contact portion 221 extends into the housing 11. When the operation member 22 slides upward, the contact portion 221 pushes the driving member 24 upward to compress the second biasing element 25, at this moment, the driving surface 241 is no longer in contact with the limiting member 21. The driving member 24 is further formed with a second surface 242. When the driving member 24 moves upward until the second surface 242 is aligned with the limiting member 21, the limiting member 21 is no longer squeezed by the driving surface 241, at this moment, the driving member 24 allows the limiting member 21 to disengage from the contact of the first rotation member 51, so that the user may pull out the first execution assembly 50.

As shown in FIG. 8, the first rotation member 51 is further formed with a first ring-shaped groove 512. The first ring-shaped groove 512 surrounds the first axis 101, and the first groove 511 is disposed in the first ring-shaped groove 512. The first groove 511 is recessed toward the first axis 101 relative to the first ring-shaped groove 512, and a plurality of first grooves 511 are provided. It can be understood that one first groove 511 may also be provided. In this way, when the first rotation member 51 is inserted into the driving hole 131, the first groove 511 may not be aligned with the limiting member 21, and the limiting member 21 may be firstly inserted into first ring-shaped groove 512; at this moment, the limiting member 21 is in contact with the first ring-shaped groove 512 and the third surface 243 formed by the driving member 24, respectively, the first rotation member 51 will not disengaged from the main shaft 13 along the first axis 101, but is rotatable by a certain angle relative to the main shaft 13; and then, when the user rotates the first rotation member 51 or the motor is turned on, the limiting member 21 moves into the first groove 51, so that the first rotation member 51 is non-rotatable relative to the main shaft 13. Where, the third surface 243 is disposed between the first surface and the second surface 142, a distance between the third surface 243 and the first axis 101 is greater than a distance between the first surface and the first axis 101, and a distance between the third surface 243 and the axis 101 is less than a distance between the second surface 242 and the first axis 101.

Similarly, the second rotation member 61 is formed with a second groove 611 having substantially the same structure as the first groove 511, and the third rotation member 71 is formed with a third groove 711 having substantially the same structure as the first groove 511.

The housing 11 has a straight cylindrical shape, which reduces the occupied space and is convenient for use and transportation. As shown in FIG. 3, FIG. 10 and FIG. 12, the motor 12 is an outer rotor motor, and the motor 12 includes an outer rotor 123. A circuit board 17 is disposed in the housing 11. The motor 12 includes an output line 122 electrically connected to the circuit board 17, and the output line 122 is located between the motor 12 and the transmission assembly 14. The outer rotor motor has a smaller volume, occupies less space, provides greater torque, and reduces the whole volume of the polishing machine 100. The arrangement of the position of the output line 122 fully utilizes the space between the motor 12 and the transmission assembly 14, reduces the volume of the housing 11 of the polishing machine 100, and facilitates use and transportation. In the present example, the motor 12 is a brushless sensorless motor. The brushless sensorless motor is not provided with a Hall sensor, and is configured to detect the change of the back electromotive force of the motor 12 through the electronic controller so as to determine the position of the outer rotor 123 of the motor 12 to realize the direction change. Therefore, the brushless sensorless motor is simpler in structure, less in volume and weight, and more compact and portable in the whole structure relative to other motors.

In one example, the housing 11 is configured to be separated from the outer rotor 123 of the motor 12, preventing the housing 11 from interfering with the outer rotor 123 of the motor 12.

A centrifugal fan 124 is disposed at one end of the motor 12, and an axial fan 125 is disposed at another end of the motor 12. The centrifugal fan 124 is located at one of the motor 12 facing toward the transmission assembly 14. The axial fan 125 is configured to guide airflow to flow into an exterior of the housing 11 from an interior of the housing 11. The airflow flows into the interior of the housing 11 from the exterior of the housing 11, and then flows through the motor 12, and finally flows out of the housing 11, so that the heat in the housing 11 may be taken away and the motor 12 is subject to better heat dissipation.

As shown in FIG. 12, the motor 12 further includes a stator core 126, a stator coil 127, a stator supporter 128, and the outer rotor 123. The stator coil 127 is wound onto the stator core 126, and the stator supporter 128 supports the stator core 126. The outer rotor 123 is connected to the motor shaft 121. The axial fan 125 is fixedly connected to the motor shaft 121. The centrifugal fan 124 is fixedly connected to the outer rotor 123. An air guiding cover 18 is disposed outside the motor 12. The air guiding cover 18 includes a surrounding portion 181 and an air guiding portion 182. The surrounding portion 181 surrounds the outer rotor 123. The surrounding portion 181 is spaced from an outer wall of the outer rotor 123 by a certain distance. In other words, the surrounding portion 181 is not in contact with the outer rotor 123, and the air guiding cover 18 is fixed to the housing 11, which prevents the air guiding cover 18 from interfering with the rotation of the outer rotor 123. The surrounding portion 181 may be spaced from the housing 11 by a certain distance, so that the output line 122 may extend along a gap between the surrounding portion 181 and the housing 11, and the output line 122 is protected by the surrounding portion 181 and is not in contact with the outer rotor 123. The air guiding portion 182 is configured to guide the airflow to flow toward a lower side of the motor 12, thereby preventing the heat accumulation in the housing 11 and improving the heat dissipation effect.

The stator supporter 128 is further fixedly connected to the inner housing 15, further improving the sealing effect.

An air outlet 11 a is disposed on a position of the housing 11 corresponding to the centrifugal fan 124, and an air inlet 11 b is disposed on a position of the housing 11 adjacent to the coupling portion 113. A heat dissipation passage is formed between the air inlet 11 b and the air outlet 11 a, so as to dissipate heat from the motor 12 and improve cooling effect.

The circuit board 17 is disposed in the handle portion 111, and located between the motor 12 and the coupling portion 113. The circuit board 17 is located on a rear side of the circuit board 17, so that the heat dissipation airflow may simultaneously dissipate heat from the circuit board 17 and the motor 12.

As shown in FIG. 2 and FIG. 3, the polishing machine 100 further includes an operation switch 19 for controlling the on-off of the motor 12. The operation switch 19 is movably connected to the housing 11, and the operation switch 19 may move relative to the housing 11 at least to a first operation position and a second operation position. When the operation switch 19 is in the first operation position, the motor 12 is rotated at a first rotation speed; when the operation switch 19 is in the second operation position, the motor 12 is rotated at a second rotation speed; where the first rotation speed and the second rotation speed each are greater than zero. In other words, the operation switch 19 may not only turn on and turn off the motor 12, but also adjust rotation speed of the motor 12. In one example, the operation switch 19 may perform stepless rotation speed adjustment on the motor 12, and the operation switch 19 is a stroke switch, which is movable relative to the housing 11 and has a plurality of positions corresponding to a plurality of rotation speeds of the motor 12. In the present example, the operation switch 19 is disposed on the top of the handle portion 111 to facilitate the operation.

The housing 111 extends along a second straight line 107 parallel to the rotation axis 106. The operation switch 19 is slidably connected with the housing 11 substantially along the second straight line 107, or the operation switch 19 is rotatable relative to the housing 11 about an axis parallel to the rotation axis 106. When the user grips the handle portion 111, the four fingers of the human hand are bent, the thumb of the human hand extends substantially along the second straight line 107, and the user may use the thumb to operate the operation switch 19 along the second straight line 107.

The operation switch 19 is a slide switch, such as a push button, substantially extending along the second straight line 107, and the operation switch 19 is slidably connected with the housing 11 substantially along the second straight line 107.

As shown in FIG. 13 and FIG. 14, the operation switch 19 is substantially divided into a first operation portion 191 and a second operation portion 192 along a front-rear direction. The first operation portion 191 and the second operation portion 192 are the same in the length along the first-rear direction. In other words, if the operation switch 19 is regarded as a lever, a fulcrum of the lever is located between the first operation portion 191 and the second operation portion 192, where the first operation portion 191 is located on a front side, and the second operation portion 192 is located on a rear side. The housing 11 is formed with a stop portion 11 c. When the user only applies a force along the second straight line 107 to the first operation portion 192, the operation switch 19 may only slide relative to the housing 11 to the stop portion 11 c; at this moment, the second operation portion 192 needs to be further depressed to bypass the stop portion 11 c. When the user applies an oblique downward force to the second operation portion 192, the first operation portion 191 is lifted slightly upward, the operation portion 19 may directly bypass the stop portion 11 c to slide forward relative to the housing 11 along the first straight line 105.

The operation switch 19 is further provided with a fixing portion 193 for fixing the operation switch 19 to a preset position of the housing 11, and the housing 11 is provided with a cooperation portion 11 d for cooperating with the fixing portion 193. In one example, the fixing portion 193 is disposed at the bottom of the operation switch 19, and extends along a direction perpendicular to the second straight line 107. In one example, the cooperation portion 11 d is a passage allowing at least part of the fixing portion 193 to pass through.

When the operation switch 19 moves relative to the housing 11 to a preset position, the motor 12 has a maximum rotation speed which is greater than the rotation speed of the motor 12 when the operation switch 19 is at any position other than the preset position. When the rotation speed of the motor 12 needs to be maintained at the maximum rotation speed, the user operates the second operation portion 192 to push the operation switch 19 to the preset position and then depress the first operation portion 191, such that the fixing portion 193 of the operation switch 19 is inserted into the cooperation portion 11 d; and then the user releases the operation switch 19 to keep the operation switch 19 at the preset position, so that the motor 12 may run at the maximum rotation speed all the time.

The polishing machine 100 further includes at least one speed governing member 194, and the motor 12 has at least two different gear rotation speeds. The speed governing member 194 is configured for adjusting the maximum rotation speed to a preset gear rotation speed, and the maximum rotation speed is equal to the preset gear rotation speed. In other words, the speed governing member 194 is configured for quickly adjusting the maximum rotation speed of the motor 12. In the present example, two speed governing members 194, namely increasing and decreasing, are provided, and four gear rotation speeds are provided. When the user operates the speed governing members 194, the rotation speed of the motor 12 may be quickly switched between the four gear rotation speeds so as to switch the preset gear rotation speed to one of the four gear rotation speeds. At the same time, since the maximum rotation speed of the motor 12 is equal to the preset gear rotation speed, the rotation speed of the motor 12 may only be switched between zero and the preset gear rotation speed when the user adjusts the stroke of the operation switch 19.

In one example, the speed governing member 194 is a button-type member, and the user may depress the speed governing member 194 to adjust the gear rotation speed of the motor 12. In the present example, the housing 11 is provided with two speed governing members 194, namely a speed increasing button and a decreasing button. The increasing button is marked with a plus sign and the decreasing button is marked with a minus sign, which is convenient for the user to identify. A gear light is disposed adjacent to the speed governing member 194, so that the gear rotation speed of the motor 12 is visualized. In one example, a same number of gear lights and gear rotation speeds is provided. In the present example, the motor 12 is provided with four different gear rotation speeds, which are a first-level gear rotation speed to a fourth-level gear rotation speed, respectively; therefore, four gear lights are provided. When the gear rotation speed is the first-level gear rotation speed, one gear light is turned on; when the gear rotation speed is the second-level gear rotation speed, two gear lights are turned on, and so on.

In the present example, a process of moving the operation switch 19 to the stop portion 11 c from the turn-on position is defined as a low-speed stage. In other words, during the process of moving the operation switch 19 to the stop portion 11 c from the turn-on position, the motor 12 is rotated at a rotation speed less than or equal to the preset rotation speed all the time. When the motor 12 needs to rotate at a low speed in a short time, the user may only operate the first operation portion 191 to stop the operation switch 19 at the stop portion 11 c, and does not need to operate the second operation portion 192, thereby facilitating the user's multi-scenario operation.

A reciprocal of a ratio of a change value of the moving stroke of the operation switch 19 to a change value of the corresponding rotation speed of the motor 12 is defined as a speed governing rate. The operation switch 19 is further provided with a high speed stage in which the motor 12 is rotated at a rotation speed greater than or equal to the preset rotation speed, and a speed governing rate in the high speed stage is greater than a speed governing rate in the low speed stage. In the present example, a process where the operation switch 19 bypasses the gear portion and moves to the preset position is a high speed stage. In the high speed stage and the low speed stage, the rotation speed of the motor 12 is linearly changed with the stroke of the operation switch 19. In other words, the speed governing rates in the low and high speed stage each are fixed values, and the speed governing rate in the high speed stage is greater than the speed governing rate in the low speed stage. The design of the speed governing rate is more suitable for the use scenario of the polishing machine 100, enables that the rotation speed is quickly increased to the maximum rotation speed to perform polishing after the polishing liquid is fully spread, and has higher practicality.

The basic principles, main features and advantages of the present disclosure have been shown and described above. It is to be understood by any person skilled in the art that the foregoing examples are not intended to limit the present disclosure in any form. All technical solutions obtained by equivalent substitution or equivalent transformation are within the scope of the present disclosure. 

What is claimed is:
 1. A polishing machine, comprising: a housing comprising a handle portion for a user gripping; a motor disposed in the housing; a main shaft rotatable relative to the housing about a first axis; a first execution assembly configured for connecting to a first accessory, wherein the first execution assembly comprises a first rotation member and a first output member, the first rotation member is configured for connecting to the main shaft, the first rotating member is capable of being driven by the main shaft to rotate about the first axis when connected with the main shaft, the first output member comprises a first driving portion for connecting with the first accessory so as to drive the first accessory to rotate about a second axis, and the second axis coincides with the first axis; a second execution assembly configured for connecting to a second accessory, wherein the second execution assembly comprises a second rotation member and a second output member, the second rotation member is configured for connecting to the main shaft, the second rotating member is capable of being driven by the main shaft to rotate about the first axis when connected with the main shaft, the second output member comprises a second driving portion for connecting to the second accessory to drive the second accessory, the second output member is rotatable relative to the second rotation member about a third axis, the third axis is parallel to the first axis, and a distance between the third axis and the first axis is greater than or equal to 1 mm and less than or equal to 12 mm; a limiting member movable between a first position and a second position, wherein the limiting member is configured to, in condition that the limiting member is at the first position, prevent the first rotation member or the second rotation member from moving relative to the main shaft; and the limiting member is further configured to, in condition that the limiting member is at the second position, allow the first rotation member or the second rotation member to move relative to the main shaft; and an operation member configured to, in condition that the operation member is operated, allow the limiting operation to disengage from the first position.
 2. The polishing machine according to claim 1, further comprising a first biasing element configured to generate a biasing force for driving the operation member to reset.
 3. The polishing machine according to claim 2, wherein the housing comprises a head housing configured for accommodating the main shaft, the operation member is sleeved outside the head housing, and the operation member is slidable relative to the head housing along the first axis.
 4. The polishing machine according to claim 3, wherein the head housing is further fixedly connected with a guiding member, and the guiding member is configured for guiding the operation member to slide and is made of metal.
 5. The polishing machine according to claim 4, wherein the operation member surrounds the first axis, and the operation member protrudes downward out of the guiding member.
 6. The polishing machine according to claim 3, wherein the first biasing element is a spring at least part of which is sleeved outside the head housing, and the spring is located between the head housing and the operation member.
 7. The polishing machine according to claim 3, further comprising a transmission assembly configured for transmitting power between the motor and the main shaft and an inner housing configured for accommodating the transmission assembly and disposed in the housing, wherein both the operation member and the limiting member are disposed outside the inner housing.
 8. The polishing machine according to claim 3, wherein the limiting member is a sphere, the main shaft is formed with a driving hole for the first rotation member or the second rotation member inserting into, a hole wall of the driving hole is formed with an accommodating hole for accommodating at least part of the sphere, the sphere is movable to the first position and the second position along a first straight line perpendicular to the first axis in the accommodating hole, at least part of the sphere extends into the driving hole when the sphere is located at the first position, and the sphere is located outside the driving hole when the sphere is located at the second position.
 9. The polishing machine according to claim 8, further comprising a second biasing element configured to generate a biasing force for driving the limiting member to move toward the first position, and the second biasing element is a spring sleeved onto the main shaft.
 10. The polishing machine according to claim 9, wherein the first rotation member is formed with a first groove for receiving the sphere, and the second rotation member is formed with a second groove for receiving the sphere.
 11. The polishing machine according to claim 1, wherein the first output member and the first rotation member are integrally formed, and the first driving portion is a hole or a post centered on the first axis.
 12. The polishing machine according to claim 1, wherein the first driving portion is a hole or a post centered on the second axis, and the second driving portion is a hole or a post centered on the third axis.
 13. The polishing machine according to claim 1, further comprising a transmission assembly configured for transmitting power between the motor and the main shaft and an inner housing configured for accommodating the transmission assembly and disposed in the housing wherein the limiting member are disposed outside the inner housing.
 14. The polishing machine according to claim 1, further comprising a third execution assembly configured for connecting to a third accessory, wherein the third execution assembly comprises: a third rotation member configured for connecting to the main shaft, wherein the third rotating member is capable of being driven by the main shaft to rotate about the first axis when connected with the main shaft; and a third output member comprising a third driving portion which is configured for connecting to the third accessory to drive the third accessory, wherein the third output member is rotatable relative to the third rotation member about a fourth axis, the fourth axis is parallel to the first axis, and a distance between the fourth axis and the first axis is greater than or equal to 1 mm and less than or equal to 3 mm.
 15. A polishing machine, comprising: a housing comprising a handle portion for a user gripping; a motor disposed in the housing; a main shaft rotatable relative to the housing about a first axis; a first execution assembly configured for connecting to a first accessory, wherein the first execution assembly comprises a first rotation member and a first output member, the first rotation member is configured for connecting to the main shaft, the first rotating member is capable of being driven by the main shaft to rotate about the first axis when connected with the main shaft, the first output member comprises a first driving portion for connecting to the first accessory to drive the first accessory, the first output member is rotatable relative to the first rotation member about a second axis, the second axis is parallel to the first axis, and a distance between the second axis and the first axis is greater than or equal to 1 mm and less than or equal to 3 mm; a second execution assembly configured for connecting to a second accessory, wherein the second execution assembly comprises a second rotation member and a second output member, the second rotation member is configured for connecting to the main shaft, the second rotating member is capable of being driven by the main shaft to rotate about the first axis when connected with the main shaft, the second output member comprises a second driving portion for connecting to the second accessory to drive the second accessory, the second output member is rotatable relative to the second rotation member about a third axis, the third axis is parallel to the first axis, and a distance between the third axis and the first axis is greater than or equal to 1 mm and less than or equal to 12 mm; a limiting member movable between a first position and a second position, wherein the limiting member is configured to, in condition that the limiting member is at the first position, prevent the first rotation member or the second rotation member from moving relative to the main shaft; and the limiting member is further configured to, in condition that the limiting member is at the second position, allow the first rotation member or the second rotation member to move relative to the main shaft; and an operation member configured to, in condition that the operation member is operated, allow the limiting operation to disengage from the first position.
 16. The polishing machine according to claim 15, wherein the distance between the second axis and the first axis is less than the distance between the third axis and the first axis.
 17. The polishing machine according to claim 15, further comprising a first biasing element configured to generate a biasing force for driving the operation member to reset, wherein the housing comprises a head housing configured for accommodating the main shaft, the first biasing element is a spring at least part of which is sleeved outside the head housing, the spring is located between the head housing and the operation member, the operation member is sleeved outside the head housing, and the operation member is slidable relative to the head housing along the first axis.
 18. The polishing machine according to claim 17, wherein the head housing is further fixedly connected with a guiding member, and the guiding member is configured for guiding the operation member to slide and is made of metal, and the operation member surrounds the first axis, and protrudes downward out of the guiding member.
 19. The polishing machine according to claim 15, further comprising a transmission assembly configured for transmitting power between the motor and the main shaft and an inner housing configured for accommodating the transmission assembly and disposed in the housing wherein both the operation member and the limiting member are disposed outside the inner housing.
 20. A polishing machine, comprising: a housing comprising a handle portion for a user gripping; a motor disposed in the housing; a main shaft rotatable relative to the housing about a first axis; a first execution assembly configured for connecting to a first accessory, wherein the first execution assembly comprises a first rotation member and a first output member, the first rotation member is configured for connecting to the main shaft, the first rotating member is capable of being driven by the main shaft to rotate about the first axis when connected with the main shaft, the first output member comprises a first driving portion for connecting to the first accessory to drive the first accessory, the first output member is rotatable relative to the first rotation member about a second axis, the second axis is parallel to the first axis, and a distance between the second axis and the first axis is greater than or equal to 1 mm and less than or equal to 12 mm; a limiting member movable between a first position and a second position, wherein the limiting member is configured to, in condition that the limiting member is at the first position, prevent the first rotation member from moving relative to the main shaft; and the limiting member is further configured to, in condition that the limiting member is at the second position, allow the first rotation member to move relative to the main shaft; and an operation member configured to, in condition that the operation member is operated, allow the limiting operation to disengage from the first position. 